1. Field of the Invention
The present invention relates to a portable personal device having facilities for storing and playing digital information (hereinafter, referred to as contents), and more particularly, to a method of controlling a portable personal device having facilities for storing and playing digital contents through a computer and the operation method of a portable personal device therefor. The present application is based on Korean Patent Application No. 00-2224, which is incorporated herein by reference.
2. Description of the Related Art
Among portable personal devices which have facilities for storing and playing sound, there is a small size cassette player. When a cassette player has recording facilities for voice or musical sound, it is referred to as a cassette recorder. Contents recorded or reproduced by the cassette player or cassette recorder are analog-type data.
However, in line with the development of digital technologies, such as a small size compact disc (CD) player, the portable personal device which can store contents in a digital format and has facilities for reproducing these digital data, has been developed. Generally, a CD player which adopts a digital format does not offer a recording function, but gives an improved sound quality compared to that of an analogue-type cassette player.
Also, in line with development of computer-related technologies, particularly with development of multimedia technologies, contents can be produced and stored in a variety of digital format files, and software players which can reproduce contents stored in these digital files through a computer have been developed. Among the types of those digital files, there are Microsoft's wave, Progressive Network's real audio (ra), and moving picture experts group (MPEG)'s MP3(MPEG1 Layer 3). Also, contents which can be stored in a digital file in a computer can include not only voice or musical sound, but also images. Among the types of these image files, are quicktime image, MPEG image, etc.
Meanwhile, next-generation products in which computer digital technologies are applied to a portable personal device, such as a hardware player, are being developed. The MP3 player is one example of these products.
The MP3 player manages digital contents in a memory in the form of a file and has a central processing unit (CPU) for controlling internal operations. Generally, having a serial port or parallel port, the MP3 player has communication functions (for example, a function for downloading a file) through a serial or parallel cable to a computer.
At present, however, there exist no standardized protocols defining a communication method between the MP3 player and a computer. Therefore, each MP3 player developer develops its own application program to support communications with its MP3 player so that communications between a computer and the MP3 player can be supported. However, this results in lack of compatibility between MP3 systems of different developers, because they each developed their own respective communication methods between an MP3 player and a computer. That is, the MP3 player of each MP3 developer can communicate only with a computer that has the communication application program of its own MP3 developer, and cannot communicate with those computers that have communication application programs of other MP3 developers.
The lack of compatibility due to the lack of a standardized communication protocol hinders mass production, and also puts barriers in the development period of communication application programs, and in quality verification of MP3 players. Also, the lack of a standardized communication protocol causes the entire communication module of an MP3 player and the corresponding communication program of a computer to be remade, when new functions are added or new models or products are developed.